With the development of data storage techniques, various data storage devices now provide users with higher and higher data storage capacity, and also their speed of accessing data has been increased greatly. So far various RAID-based data storage systems have been developed to increase data reliability. When one or more disks in a storage system fail, a new standby disk needs to be introduced into the storage system, and data in failing disks can be recovered from data in other disks operating normally.
During data recovery, recovered data needs to be written to the backup disk. Due to bandwidth limitation of a data interface of the standby disk, when a large amount of data needs to be recovered, the time for data recovery might amount to several hours and even a couple of days. As the storage capacity of the storage system increases constantly, the time for data recovery might reach an unbearable degree. At this point, how to reduce the time for data recovery and further improve performance of the storage system becomes a focus for research.